U.S. patent application number 16/880309 was filed with the patent office on 2020-09-10 for compositions and methods for long term release of gonadotropin-releasing hormone (gnrh) antagonists.
The applicant listed for this patent is VERU INC.. Invention is credited to Andrew Michael CERRO, Ravi KACKER, Jui-Chen LIN, Christopher A. RHODES, Mitchell S. STEINER.
Application Number | 20200282008 16/880309 |
Document ID | / |
Family ID | 1000004871545 |
Filed Date | 2020-09-10 |
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United States Patent
Application |
20200282008 |
Kind Code |
A1 |
KACKER; Ravi ; et
al. |
September 10, 2020 |
COMPOSITIONS AND METHODS FOR LONG TERM RELEASE OF
GONADOTROPIN-RELEASING HORMONE (GnRH) ANTAGONISTS
Abstract
The invention provides compositions and methods for long term
release of gonadotropin-releasing hormone (GnRH) antagonists and
uses thereof. Specifically, the invention provides polymer
compositions and methods for controlled release of GnRH
antagonists.
Inventors: |
KACKER; Ravi; (LEXINGTON,
MA) ; STEINER; Mitchell S.; (GERMANTOWN, TN) ;
LIN; Jui-Chen; (San Diego, CA) ; CERRO; Andrew
Michael; (SAN DIEGO, CA) ; RHODES; Christopher
A.; (SAN DIEGO, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VERU INC. |
Miami |
FL |
US |
|
|
Family ID: |
1000004871545 |
Appl. No.: |
16/880309 |
Filed: |
May 21, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15974461 |
May 8, 2018 |
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16880309 |
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15885464 |
Jan 31, 2018 |
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15974461 |
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62452788 |
Jan 31, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 9/06 20130101; A61P
5/26 20180101; A61K 47/34 20130101; A61K 38/09 20130101; A61K
9/0024 20130101; A61P 35/00 20180101 |
International
Class: |
A61K 38/09 20060101
A61K038/09; A61K 9/06 20060101 A61K009/06; A61K 47/34 20060101
A61K047/34; A61P 35/00 20060101 A61P035/00; A61P 5/26 20060101
A61P005/26; A61K 9/00 20060101 A61K009/00 |
Claims
1. A method for decreasing the level of testosterone in a subject
in a cetrorelix treatment comprising administering to the subject a
composition of multi-block copolymer, a biocompatible polar aprotic
solvent, and cetrorelix, wherein the level of cetrorelix is
maintained at more than 2 ng/mL in the subject.
2. The method according to claim 1, wherein the composition
releases cetrorelix for three, six, nine, or twelve months.
3. The method according to claim 2, wherein the multi-block
copolymer has at least one of poly-lactic, co-glycolic acid,
poly-lactic acid, poly-glycolic acid, polyethylene glycol, poly
(3-hydroxybutyrate), or polycaprolactone.
4. The method according to claim 3, wherein the multi-block
copolymer has poly-lactic and co-glycolic acid in a molar ratio
between about 1:1 to about 6:1 poly-lactic acid:poly-glycolic
acid.
5. The method according to claim 1, wherein the biocompatible polar
aprotic solvent is at least one of N-methyl-2-pyrrolidone,
2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide,
dimethyl sulfoxide, propylene carbonate, caprolactam, triacetin,
benzyl benzoate, or propylene glycol.
6. The method according to claim 5, wherein the biocompatible polar
aprotic solvent is N-methyl-2-pyrrolidone.
7. The method according to claim 1, wherein the cetrorelix is
present in an amount of at least 5% of the weight of the
composition.
8. The method according to claim 1, wherein composition has an area
under the curve between 10000 ng/ml*hr and 30000 ng/ml*hr.
9. The method according to claim 1, wherein the composition is in
the form of a microsphere, hydrogel, or flowable composition.
10. The method according to claim 1, wherein the composition is a
hydrogel.
11. The method according to claim 10, wherein the composition is
biodegradable.
12. The method according to claim 1, wherein the cetrorelix is
present in an amount of about 50 mg to about 300 mg.
13. The method according to claim 1, wherein the cetrorelix
treatment treats a disease associated with gonadotropin-releasing
hormone (GnRH).
14. The method according to claim 13, wherein the cetrorelix
treatment comprises suppression of testosterone, FSH, and LH
production for the treatment of prostate cancer and benign
prostatic hyperplasia, directly blocking GnRH receptors on prostate
cells for treatment of prostate cancer and benign prostatic
hyperplasia, controlled ovarian stimulation for assisted
reproductive techniques, treatment of uterine myoma, suppression of
ovarian function while undergoing chemotherapy, treatment of breast
cancer, treatment of ovarian cancer, male contraception, and female
contraception.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part application of
U.S. application Ser. No. 15/974,461, filed May 8, 2018, which is a
continuation-in-part application of U.S. application Ser. No.
15/885,464, filed Jan. 31, 2018, which claims priority to and the
benefit of U.S. Provisional Application 62/452,788, filed Jan. 31,
2017, incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The invention relates to compositions and methods for long
term release of gonadotropin-releasing hormone (GnRH) antagonists
and uses thereof. Specifically, the invention relates to
polymer-based compositions and methods for controlled release of
GnRH antagonists.
BACKGROUND OF THE INVENTION
[0003] The hypothalamic hormone, gonadotropin-releasing hormone
(GnRH) (also known as luteinizing hormone releasing hormone
(LHRH)), controls the secretion of the gonadotropins, luteinizing
hormone (LH) and follicle stimulating hormone (FSH) from the
anterior pituitary gland. Analogues of GnRH are currently used to
treat many medical conditions that require manipulation of the
production of the sex hormones, testosterone and estrogen. Schally
et al. (Schally 1971) isolated, identified the amino acid sequence,
and synthesized the peptide hormone GnRH. Deletion or replacement
of different amino acids of GnRH peptide has resulted in the
discovery of distinct GnRH agonist analogues that demonstrate
greater relative potency for the secretion of LH and FSH. A
paradoxical clinical effect occurs when agonistic analogues are
used continuously such that after the chronic, and relatively long
period (2-3 weeks) of stimulation of the secretion of LH and FSH,
there is actually an inhibition of LH and/or FSH release and
consequent suppression of sex steroid production (testosterone and
estrogen). (Reissmann 2000). In certain medical conditions,
however, an immediate and dose-dependent suppression of LH and FSH
is desired. Over 20 years ago, Schally and Revier synthesized the
Pt generation analogues of GnRH antagonist analogues which were too
lipophilic and induced histamine release. (Schmidt 1984; Hahn
1985). The 2.sup.nd generation GnRH antagonist analogues were made
by incorporating further amino acid substitutions (Bajusz 1988;
Rivier 1993) that resulted in potentially safer and more effective
decapeptide analogues. Examples of newer generation GnRH antagonist
analogues include degarelix, ganirelix, ozarelix, cetrorelix,
taverelix, antarelix, and iturelix.
[0004] Clinical development and medical applications of these GnRH
antagonist analogues have been either successful or attempted for
controlled ovarian stimulation for assisted reproductive
techniques, uterine myoma, ovarian cancer, benign prostatic
hyperplasia, and prostate cancer. In certain diseases and
conditions, the major limitation for successful application of the
GnRH antagonist analogue has been having only a short acting
formulation where longer acting depot formulations would be more
clinically advantageous for optimal drug compliance.
[0005] Accordingly, there exists a need for very long acting
controlled or extended release formulations of a GnRH antagonist
(also called a LHRH antagonist).
SUMMARY OF THE INVENTION
[0006] In one aspect, the invention relates to a long-term drug
release composition comprising: a therapeutically effective amount
of a GnRH antagonist in combination with a multi-block copolymer,
wherein the composition releases the GnRH antagonist for a duration
of at least six months.
[0007] In another aspect, the invention relates to a flowable
composition, the composition comprising: (a) a multi-block
copolymer; (b) a biocompatible polar aprotic solvent, wherein the
biocompatible polar aprotic solvent is miscible to dispersible in
aqueous medium or body fluid; and (c) a therapeutically effective
amount of a GnRH antagonist, wherein the flowable composition
releases the GnRH antagonist for a duration of at least four
months. In exemplary embodiments of the compositions, the GnRH
antagonist is cetrorelix, degarelix, ganirelix, ozarelix,
taverelix, antarelix, or iturelix. In various embodiments, the
multi-block copolymer is polyglycolide (PLG), polylactide (PLA), or
poly-lactic co-glycolic acid (PLGA).
[0008] In another aspect, the invention relates to a composition
for a long-term release of cetrorelix, the composition comprising a
multi-block copolymer, a solvent, and a therapeutically effective
amount of cetrorelix, and the release of cetrorelix duration is at
least six months.
[0009] In another aspect, the invention relates to a method to
extend the release of cetrorelix in a subject for a duration of at
least six months. The method comprising administering to the
subject a composition comprising cetrorelix and a multi-block
copolymer. Wherein the multi-block copolymer comprises poly-lactic
co-glycolic acid (PLGA) in a lactide:glycolide molar ratio between
1:1, 1:0, and 0:1. Wherein cetrorelix is present in an amount of
5%-90% of the weight of the composition, and the multi-block
copolymer is present in an amount of 10%-50% of the weight of the
composition. In other embodiments, the composition comprises
cetrorelix and a multi-block copolymer, the multi-block copolymer
comprising poly-lactic co-glycolic acid (PLGA) in a
lactide:glycolide molar ratio of 3:1. In certain embodiments, the
composition comprises cetrorelix and a multi-block copolymer. The
multi-block copolymer comprising poly-lactic co-glycolic acid
(PLGA) in a lactide:glycolide molar ratio of 5.67:15.
[0010] In another aspect, the invention relates to a method to
maintain a therapeutic level of cetrorelix in a subject for a
duration of at least six months. The method comprising
administering to the subject a composition comprising cetrorelix
and a multi-block copolymer. The multi-block copolymer comprising
poly-lactic co-glycolic acid (PLGA) in a lactide:glycolide molar
ratio between 1:1, 1:0 and 0:1. Wherein cetrorelix is present in an
amount of 5%-90% by the weight of the composition, and the
multi-block copolymer is present in an amount of 10%-50% by the
weight of the composition.
[0011] In another aspect, the invention relates to a composition
comprising: a therapeutically effective amount of a GnRH antagonist
in combination with a multi-block copolymer. Wherein the
multi-block copolymer comprises polyethyleneglycol(PEG)-PLGA-PEG,
poly(3-hydroxybutyrate), PCL, poly(glycolide) (PLG), poly(lactide)
(PLA), poly-lactic co-glycolic acid (PLGA) or a combination
thereof. Wherein the composition achieves a therapeutic effect
within 24 hours and maintains therapeutic effect for at least 180
days. In an exemplary embodiment, GnRH antagonist is cetrorelix,
degarelix, ganirelix, ozarelix, taverelix, antarelix, or
iturelix.
[0012] In another aspect, the invention relates to a composition
comprising: a therapeutically effective amount of a GnRH antagonist
in combination with a multi-block copolymer. Wherein the
multi-block copolymer comprises randomly or non-alternatingly
arranged hydrolysable segments. Wherein each segment comprises
pre-polymer A or pre-polymer B, and wherein the segments are
operably linked to each other by a multifunctional chain extender.
Wherein the composition achieves a therapeutic effect within 24
hours and maintains therapeutic effect for at least 180 days.
[0013] In another aspect, the invention relates to a method for
treating a disease or condition associated with
gonadotropin-releasing hormone (GnRH). The method comprising
administering to a subject a composition of any of the above, or
below, embodiments, thereby treating the disease in the subject.
Wherein the composition achieves a therapeutic effect within 24
hours and maintains therapeutic effect for at least 180 days.
[0014] In another aspect, the invention relates to a composition,
the composition comprising: a therapeutically effective amount of a
GnRH antagonist in combination with a non-PLGA multi-block
copolymer. In one aspect the multi-block copolymer is
biodegradable. In another aspect the multi-block copolymer is a
thermoplastic polyester that is substantially insoluble/stable in
an aqueous medium or body fluid.
[0015] In one aspect the multi-block copolymer is at least one of
polyethylene glycol (PEG), PLG, PLA, polybutylene terephthalate
(PBT), poly(epsilon-caprolactone) (PCL), dioxanone,
butanediisocyanate, butanediol, polyoxyethylene, polypropylene,
polyoxypropylene, polystyrene, poly methyl methacrylate. Wherein
the composition releases the GnRH antagonist for a long term.
[0016] In another aspect, the invention relates to a flowable
composition, the composition comprising: (a) a biodegradable
thermoplastic polyester that is at least substantially
insoluble/stable in aqueous medium or body fluid; (b) a
biocompatible solvent, wherein the biocompatible solvent is
miscible to dispersible in aqueous medium or body fluid; and (c) a
therapeutically effective amount of a GnRH antagonist.
[0017] In another aspect, the invention relates to a flowable
composition, the composition comprising: (a) a biodegradable
thermoplastic polyester that is at least substantially
insoluble/stable in aqueous medium or body fluid; (b) a
biocompatible polar aprotic solvent, wherein the biocompatible
polar aprotic solvent is miscible to dispersible in aqueous medium
or body fluid; and (c) a therapeutically effective amount of a GnRH
antagonist.
[0018] In an exemplary embodiment, the thermoplastic polyester is a
polylactide, a polyglycolide, a polycaprolactone, a copolymer
thereof, a terpolymer thereof, or any combination thereof.
[0019] In another exemplary embodiment, the solvent is
N-methyl-2-pyrrolidone, 2-pyrrolidone, N,N-dimethylformamide,
dimethyl sulfoxide, propylene carbonate, caprolactam, triacetin,
benzyl benzoate, propylene glycol, or any combination thereof. In a
particular embodiment, the flowable composition of the invention
comprises a flowable delivery system such as an Atrigel.RTM. system
comprising a copolymer, a water-soluble organic solvent, and a
bioactive agent, for example, a GnRH antagonist.
[0020] In another aspect, the invention relates to a composition,
the composition comprising: a therapeutically effective amount of a
GnRH antagonist in combination with a multi-block copolymer,
wherein the multi-block copolymer comprises
polyethyleneglycol(PEG)-PLGA-PEG, poly(3-hydroxybutyrate), PCL,
PLG, PLA, or a combination thereof.
[0021] In another aspect, the invention relates to a composition,
the composition comprising: a therapeutically effective amount of a
GnRH antagonist in combination with a multi-block copolymer,
wherein the multi-block copolymer comprises randomly or
non-alternatingly arranged hydrolysable segments, wherein each
segment comprises pre-polymer A or pre-polymer B, and wherein the
segments are operably linked to each other by a multifunctional
chain extender. In one aspect the repeating units of the
multi-block copolymer can be the same subunit. In an exemplary
embodiment, the multi-block copolymer is a phase separated
multiblock copolymer, comprising: one or more segments of a linear
soft biodegradable pre-polymer A having a glass transition
temperature (T.sub.g) lower than 37.degree. C.; and one or more
segments of a linear hard biodegradable pre-polymer B having a
melting point temperature (T.sub.m) of 40-100.degree. C.
[0022] In another aspect, the invention relates to the use of salt
bridges or cyclization of the active agent either as a primary drug
delivery technique or in combination with another drug delivery
vehicle using compounds that include, but are not limited to,
lanthionine, dicarba, hydrazine, or lactam bridges.
[0023] In another aspect, the invention relates to the use of
micronization or stabilizing adjuvants for a long-term delivery of
a GnRH antagonist.
[0024] In another aspect, the invention relates to the use of a
solid-in-oil-in-water (S/O/W), a water-in-oil-in water (W/O/W), or
a water-oil (W/O) production method for long term delivery of a
GnRH antagonist.
[0025] In an exemplary embodiment, the composition achieves a
therapeutic effect within 24 hours and maintains therapeutic effect
for at least 90 days for >95% percent of treated patients.
[0026] In a particular embodiment, the composition is in the form
of a hydrogel. In another particular embodiment, the composition is
in the form of microspheres.
[0027] In one aspect, the composition of the invention is an
injectable composition, which is administered with one injection or
two injections administered concurrently or consecutively, with a
total injection volume, for example, less than 4 ml. Injections may
be subcutaneous or intramuscular.
[0028] In another aspect, the invention relates to a method for
extending the release of a GnRH antagonist (e.g., cetrorelix) in a
subject for a period ranging from about 1 month to about 6 months.
The method comprising administering to the subject a composition
comprising cetrorelix and a multi-block copolymer. The multi-block
copolymer comprising poly-lactic co-glycolic acid (PLGA) in a
lactide:glycolide molar ratio between 1:1, 1:0, and 0:1. Wherein
cetrorelix is present in an amount of 5%-90% of the weight of the
composition, and the multi-block copolymer is present in an amount
of 10%-50% of the weight of the composition.
[0029] In another aspect, the invention relates to a method of
maintaining a therapeutic level of a GnRH antagonist (e.g.,
cetrorelix) in a subject for a period ranging from about 1 month to
about 6 months. The method comprising administering to the subject
a composition comprising cetrorelix and a polymer. The polymer
comprising poly-lactic co-glycolic acid (PLGA) in a
lactide:glycolide molar ratio between 1:1, 1:0, and 0:1. Wherein
cetrorelix is present in an amount of 5%-90% of the weight of the
composition, and the polymer is present in an amount of 10%-50% of
the weight of the composition.
[0030] In another aspect, the composition of the invention has an
encapsulation efficiency greater than 70% and a consistent release
of the active agent from the drug delivery vehicle with no more
than 25% variation. In yet another aspect, the composition of the
invention releases the active agent from the drug delivery vehicle
with >85% intact in the active form over the entire duration of
release.
[0031] Other features and advantages of the present invention will
become apparent from the following detailed description, examples,
and figures. It should be understood, however, that the detailed
description and the specific examples while indicating preferred
embodiments of the invention are given by way of illustration only,
since various changes and modifications within the spirit and scope
of the invention will become apparent to those skilled in the art
from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 shows in vitro release of cetrorelix (CRX) from
microspheres (MSP) composed of different polymers and carriers.
[0033] FIG. 2 shows in vitro release of cetrorelix (CRX) from
microspheres (MSP) composed of different polymers loaded with
cetrorelix prepared in 35% Acetic acid/65% H.sub.2O aqueous
phase.
[0034] FIG. 3 shows daily levels of cetrorelix release from
microspheres composed of different polymers.
[0035] FIG. 4A shows the morphology of cetrorelix coated
10CP10C20-D23 beads having 12.7% cetrorelix prepared using 65%
Acetic Acid (HAc):25% water phase.
[0036] FIG. 4B shows the morphology of cetrorelix coated
20CP15C50-D23 beads comprising 13.4% cetrorelix.
[0037] FIG. 5 shows cetrorelix plasma concentration following
administration of cetrorelix PLGA gel formulations to rats.
[0038] FIG. 6A shows long term cetrorelix plasma concentration
following administration to rats of two cetrorelix salt
formulations as a suspension in water.
[0039] FIG. 6B shows plasma concentration following administration
to rats of two cetrorelix salt formulations as a suspension in
water over the first 24 hours following administration (to show
initial release).
[0040] FIG. 7A shows comparative cetrorelix plasma concentrations
in rats for PLGA gel formulations and for cetrorelix salt
formulations.
[0041] FIG. 7B shows comparative cetrorelix plasma concentrations
in rats for PLGA gel formulations and for cetrorelix salt
formulations.
[0042] FIG. 8 shows comparative cetrorelix plasma concentrations in
rats after dose normalization for PLGA gel formulations and for
cetrorelix salt formulations.
[0043] FIG. 9A shows rat serum testosterone levels following
administration of PLGA gel formulations and for cetrorelix salt
formulations over a 42 day period.
[0044] FIG. 9B shows rat serum testosterone levels following
administration of PLGA gel formulations and for cetrorelix salt
formulations over the first 24 hours following administration.
[0045] FIG. 10 shows cumulative cetrorelix in vitro release from
PLGA gel formulations.
[0046] FIG. 11 shows cumulative cetrorelix in vitro release from
RG502H/RG752H (40% PLGA)-salt microsphere formulations compared to
a PLGA gel formulation.
[0047] FIG. 12 shows cumulative cetrorelix in vitro release from
RG752H (40% PLGA) salt microsphere formulations compared to PLGA
gel formulations.
[0048] FIG. 13 shows cumulative cetrorelix in vitro release from
RG502H/RG752H (40% PLGA)-salt microsphere formulations.
[0049] FIG. 14 shows cetrorelix plasma concentration following
administration to rats of cetrorelix PLGA gel formulations
(VH-022-001, VH-023-002 and VH-024-001) for up to 119 days (17
weeks) and of cetrorelix salt formulations (Groups 4 and 5) for
.gtoreq.49 days (7 weeks). The percent day 1 release ranged from 9
to 13% of the total cetrorelix release.
[0050] FIG. 15A shows average rat serum testosterone levels
following administration of various cetrorelix PLGA gel
formulations (VH-022-001, VH-023-002 and VH-024-001) for up to 19
weeks and cetrorelix salt formulations (Groups 4 and 5). PLGA gel
formulations showed undetectable testosterone level for .gtoreq.133
days (19 weeks). Group 4 salt formulations showed undetectable
testosterone level for greater than 1 week.
[0051] FIG. 15B shows rat serum testosterone levels following
administration of various cetrorelix gel formulations and salt
formulations, as indicated in FIG. 15A, over the first week
following administration, showing undetectable testosterone levels
for all formulations after the first 24 hours.
[0052] FIGS. 16A and 16B show testosterone serum levels. FIG. 16A
shows the testosterone serum level for several gel formulations in
rats after 12 weeks. FIG. 16B is zoomed in for the 1.sup.st day of
FIG. 16A showing undetectable testosterone levels after 24
hours.
[0053] FIG. 17 shows cetrorelix levels in rats after 12 weeks for
the gel formulations of FIG. 16.
[0054] FIGS. 18A and 18B show serum cetrorelix data in dogs. FIG.
18A shows serum cetrorelix data for 19.9% RG752H, 30% RG752H, and
30% R202H solutions. FIG. 18B shows cetrorelix level 1 week prior
to dosing. LLOQ (ng/ml)=0.5. Animal D0103 (Group 2) vocalized and
struggled during dose administration. As a result, the dose was
delivered as 2 injections. The animal did receive the full dose as
no formulation appeared to have been lost due to the animal
struggling.
[0055] FIGS. 19A-19C show a comparison of rat and dog PK results
for cetrorelix in gel formulations (up to 39 weeks). FIG. 19A shows
2.sup.nd rat study results with cetrorelix levels above 1 ng/ml for
up to 39 weeks. FIG. 19B shows 1.sup.st dog study results with
cetrorelix levels above 1 ng/ml for up to 26 weeks. FIG. 19C shows
the formulation compositions and pharmacokinetic data for dogs and
rats. Similar formulations show similar results in both
species.
[0056] FIGS. 20A-20B show serum testosterone data. FIG. 20A shows
serum testosterone data for 19.9% RG752H, 30% RG752H, and 30% R202H
solutions. FIG. 20B shows testosterone level 1 week prior to
dosing. LLOQ (ng/ml)=0.01. Animal D0103 (Group 2) vocalized and
struggled during dose administration. As a result, the dose was
delivered as 2 injections. The animal did receive the full dose as
no formulation appeared to have been lost due to the animal
struggling.
[0057] FIGS. 21A-21C show rat and dog study results for
testosterone (up to 39 weeks). FIG. 21A shows 2.sup.nd rat study
results with undetectable testosterone for greater than 30 weeks.
FIG. 21B shows 1.sup.st dog study results with undetectable
testosterone for greater than 12 weeks. FIG. 21C shows the
formulation data of the cetrorelix, the dosing of the experiment,
the maximum serum concentration of the dose, and the area under the
curve of the dose.
[0058] FIGS. 22A and 22B show 1.sup.st dog study for group 1 (19.9%
RG752H solution). FIG. 22A shows serum cetrorelix level. FIG. 22B
shows serum testosterone level. These figures show that
testosterone level goes up once cetrorelix level drops less than 2
ng/mL.
[0059] FIGS. 23A and 23B show 1.sup.st dog study for group 2 (30%
RG752H solution). FIG. 23A shows serum cetrorelix level. FIG. 23B
shows serum testosterone level. These figures also show that
testosterone level goes up once cetrorelix level drops less than 2
ng/mL.
[0060] FIGS. 24A and 24B show 1.sup.st dog study for group 2 (30%
R202H solution). FIG. 24A shows serum cetrorelix level. FIG. 24B
shows serum testosterone level. These figures also show that
testosterone level goes up once cetrorelix level drops less than 2
ng/mL.
DETAILED DESCRIPTION OF THE INVENTION
[0061] The present subject matter may be understood more readily by
reference to the following detailed description which forms a part
of this disclosure. It is to be understood that this invention is
not limited to the specific products, methods, conditions or
parameters described and/or shown herein, and that the terminology
used herein is for the purpose of describing particular embodiments
by way of example only and is not intended to be limiting of the
claimed invention.
[0062] Unless otherwise defined herein, scientific and technical
terms used in connection with the present application shall have
the meanings that are commonly understood by those of ordinary
skill in the art. Further, unless otherwise required by context,
singular terms shall include pluralities and plural terms shall
include the singular.
[0063] As employed above and throughout the disclosure, the
following terms and abbreviations, unless otherwise indicated,
shall be understood to have the following meanings.
[0064] The invention relates to a controlled release composition
comprising a gonadotropin-releasing hormone (GnRH) antagonist in
combination with one or more polymers and/or salts. The GnRH
antagonist and polymer composition may be stored in solution or
suspension in a solvent suitable for both to create a stable
formulation for storage in a prefilled syringe.
[0065] The composition may include any suitable a GnRH antagonist,
known to one of skilled in the art. GnRH is also known as
follicle-stimulating hormone-releasing hormone (FSH-RH),
luteinizing hormone-releasing hormone (LHRH), gonadoliberin, and by
various other names, known to one of skilled in the art.
[0066] In a particular embodiment, the GnRH antagonist is
cetrorelix, abarelix, degarelix, ganirelix, ozarelix, taverelix,
antarelix, or iturelix.
[0067] In one aspect, provided herein is a composition. The
composition comprising a therapeutically effective amount of a GnRH
antagonist in combination with a multi-block copolymer. Wherein the
multi-block copolymer is polyglycolide (PLG), polylactide (PLA), or
poly-(lactic co-glycolic acid) (PLGA). Wherein the composition
releases the GnRH antagonist for a long term. In a particular
embodiment, the composition releases the GnRH antagonist for at
least 180 days. In certain embodiments, the composition release the
GnRH antagonist (e.g., cetrorelix) for at least 120 days. In
certain embodiments, the composition achieves a therapeutic effect
within 24 hours and maintains the therapeutic effect for at least
120 days.
[0068] In particular embodiments, the invention relates to a
composition for a long-term release of cetrorelix. The composition
comprising a biodegradable multi-block copolymer, a solvent, and a
therapeutically effective amount of cetrorelix, wherein the
long-term release is a duration of at least six months. The
composition may have a release term of about three months, six
months, nine months, or about 12 months. Preferably, the
composition has a release term of about nine months or more.
[0069] In another aspect, provided herein is a composition. The
composition comprising: a therapeutically effective amount of a
GnRH antagonist in combination with a non-PLGA multi-block
copolymer, wherein the composition releases the GnRH antagonist for
a long term. Non-PLGA multi-block copolymer are well known in the
art. Examples of a non-PLGA multi-block copolymer include, for
example, but are not limited to, polyethyleneglycol (PEG), PLG,
PLA, polybutylene terephthalate (PBT), poly(epsilon-caprolactone)
(PCL), dioxanone, butanediisocyanate, butanediol polyoxyethylene,
polypropylene, polyoxypropylene, polystyrene, poly methyl
methacrylate, or a block copolymer which additionally incorporates
one more novel amphiphilic, hydrophilic, or hydrophobic component.
In another aspect, a non-PLGA block polymer comprises a blend of
two or more multi-block copolymer types capable of releasing
therapeutically effective amount of GnRH antagonists.
[0070] In one aspect, the composition is a flowable composition
capable of forming an in situ implant in a subject. In one example,
the composition includes a biodegradable thermoplastic multi-block
copolymer, a biocompatible solvent; and a GnRH antagonist.
[0071] In another aspect, the invention relates to a flowable
composition, the composition comprising: (a) a biodegradable
thermoplastic multi-block copolymer that is at least substantially
insoluble/stable in aqueous medium or body fluid; (b) a
biocompatible polar aprotic solvent, wherein the biocompatible
polar aprotic solvent is miscible to dispersible in aqueous medium
or body fluid; and (c) a therapeutically effective amount of
cetrorelix.
[0072] The biodegradable thermoplastic multi-block copolymer can be
substantially insoluble/stable in aqueous medium or body fluid.
Biodegradable thermoplastic multi-block copolymer are well known in
the art and fully described in U.S. Pat. Nos. 6,565,874; 5,324,519;
4,938,763; 5,702,716; 5,744,153; and 5,990,194, which are
incorporated by reference herein in their entirety. In one
embodiment, biodegradable thermoplastic multi-block copolymer is a
polyester, for example, including but not limited to, a
polylactide, a polyglycolide, a polycaprolactone, a copolymer
thereof, a terpolymer thereof, or any combination thereof.
[0073] The type, amount, and molecular weight, of biodegradable
thermoplastic multi-block copolymer present in the composition may
depend upon one or more desired properties of the controlled
release implant.
[0074] Examples of types of biodegradable thermoplastic polyesters
are well known in the art and fully described in U.S. Pat. No.
6,565,874. In a particular embodiment, the suitable biodegradable
thermoplastic polyester is 1:1 poly (DL-lactide-co-glycolide)
having a carboxy terminal group or is 3:1 poly
(DL-lactide-co-glycolide) with a carboxy terminal group that is
protected. Other suitable copolymers, known to one of skilled in
the art, can also be used.
[0075] In another aspect, the PLGA multi-block copolymers in the
compositions of the present invention may have lactide:glycolide
weight ratio ranging from about 1:1 to about 1:0. In particular
embodiments, the lactide to glycolide ratio is about, 1:1, 11:9,
3:2, 13:7, 7:3, 3:1, 4:1, 5.67:1, 9:1, or 20:1.
[0076] The PLGA polymers the compositions of the present invention
may comprise a mixture of two or more PLGA multi-block copolymers
each having a different glycolide and lactide fractions. For
example, the mixture may include a first PLGA polymer having equal
amount of glycolide and lactide (RG502H) and a second PLGA polymer
having 25% glycolide and 75% lactide (RG752H). The proportions of
the first PLGA polymer and the second PLGA polymer may vary, for
example the ratio of RG502H to RG752H can range from about 1:0 to
about 0:1.
[0077] The amount of biodegradable thermoplastic multi-block
copolymer, in the composition, can be any suitable amount, known to
one of skilled in the art. The amount, in the composition, may
range from about 10 wt. % to about 80 wt. %; from about 20 wt. % to
about 60 wt. %; from about 25 wt. % to about 55 wt. %; from about
30 wt. % to about 50 wt. %; or from about 35 wt. % to about 45 wt.
%. In a particular embodiment, the amount is approximately 10, 20,
25, 30, 35, 40, 45, 50, 55, 60, 65, 70, or 80 wt. %.
[0078] The molecular weight of biodegradable thermoplastic polymer,
in the composition, can be any suitable molecular weight, known to
one of skilled in the art. The molecular weight may range from
about 10,000 to about 50,000; from about 15,000 to about 45,000;
from about 20,000 to about 40,000; or from about 20,000 to about
30,000. In a particular embodiment, the molecular weight is
approximately 10,000, 15,000, 20,000, 25,000, 30,000, 35,000,
40,000, 45,000, or 50,000.
[0079] In particular embodiments, the biodegradable thermoplastic
polyester has an average molecular weight ranging from about 15,000
to about 45,000 or from about 20,000 to about 35,000.
[0080] The biocompatible solvent can be a biocompatible solvent.
The biocompatible solvent can be a biocompatible polar aprotic
solvent. In one embodiment, the solvent is miscible to dispersible
in aqueous medium or body fluid. Suitable polar aprotic solvents
are well known in the art and fully described in, for example, in
Aldrich Handbook of Fine Chemicals and Laboratory Equipment,
Milwaukee, Wis. (2000) and U.S. Pat. Nos. 6,565,874, 5,324,519;
4,938,763; 5,702,716; 5,744,153; and 5,990,194.
[0081] In one aspect, the solvent of the invention diffuses into
body fluid so that the flowable composition coagulates or
solidifies. In another aspect, the solvent of the invention is
biodegradable. In another aspect, the solvent of the invention is
biocompatible. In yet another aspect, the solvent of the invention
is non-toxic. As set forth in U.S. Pat. No. 6,565,874, examples of
suitable polar aprotic solvents include polar aprotic solvents
having an amide group, an ester group, a carbonate group, a ketone,
an ether, a sulfonyl group, or a combination thereof.
[0082] In one embodiment, the polar aprotic solvent is
N-methyl-2-pyrrolidone, 2-pyrrolidone, N,N-dimethylformamide,
N,N-dimethylacetamide, dimethyl sulfoxide, propylene carbonate,
caprolactam, triacetin, benzyl benzoate, propylene glycol, or any
combination thereof. In another embodiment, the polar aprotic
solvent is N-methyl-2-pyrrolidone.
[0083] As set forth in U.S. Pat. No. 6,565,874, the polar aprotic
solvent can be present in any suitable amount. The type and amount
of biocompatible polar aprotic solvent present in the composition
may depend upon the desired properties of the controlled release
implant. In a particular embodiment, the type and amount of
biocompatible polar aprotic solvent influences the initial release
rate and the length of time in which the GnRH antagonist is
released from the controlled release implant.
[0084] In various embodiments of the long-term release GnRH
antagonist composition (e.g., cetrorelix), the solvent may be
present at the concentration ranging from about 10% to about 30%
(w/w). For example, the cetrorelix may be present at a
concentration ranging from about 5% to about 90% (w/w).
Alternatively, cetrorelix may be present in an amount of about 50
mg to about 300 mg or 50 mg to about 150 mg per dosage.
[0085] In certain embodiments, the composition may further comprise
a salt, i.e., a salt of the GnRH antagonist (e.g., cetrorelix).
Examples of a salt, include but are not limited to calcium pamoate
(Ca pamoate), sodium pamoate (Na pamoate) and calcium citrate (Ca
citrate). In the gel compositions, the cetrorelix may be present as
a salt, i.e., cetrorelix salt. Examples of salts include, but are
not limited to, sulfate, citrate, acetate, oxalate, chloride,
bromide, iodide, nitrate, bisulfate, phosphate, acid phosphate,
carbonate, bicarbonate, isonicotinate, lactate, salicylate, acid
citrate, tartrate, oleate, tannate, pantothenate, bitartrate,
ascorbate, succinate, maleate, gentisinate, fumarate, gluconate,
glucaronate, saccharate, formate, benzoate, glutamate,
methanesulfonate, ethanesulfonate, benzenesulfonate,
p-toluenesulfonate, camphorsulfonate, and pamoate. Preferred
examples of cetrorelix salts include cetrorelix carbonate,
cetrorelix acetate, cetrorelix benzoate, cetrorelix formate, and
cetrorelix citrate. Most preferred cetrorelix salt is cetrorelix
acetate.
[0086] In another aspect, the invention is a method of preparing a
flowable composition, the method comprising: mixing a biodegradable
thermoplastic multi-block copolymer, a biocompatible solvent; and a
GnRH antagonist. The mixing is performed for a sufficient period of
time effective to form the flowable composition for use as a
controlled release implant.
[0087] In yet another aspect, the invention is an implant formed in
situ by the process of injecting the composition of the invention
to a subject; allowing the solvent, in the composition, to
dissipate to produce a solid biodegradable implant.
[0088] In yet another aspect, the invention is a method of forming
an implant in situ in a subject, the method comprising the steps
of: injecting the composition of the invention to a subject; and
allowing the solvent, in the composition, to dissipate to produce a
solid biodegradable implant.
[0089] In one example, the flowable composition of the invention
comprises a flowable delivery system such as an Atrigel.RTM. system
comprising a multi-block copolymer, a water-soluble organic
solvent, and a bioactive agent, for example, a GnRH antagonist.
[0090] ATRIGEL.RTM. is a registered Trademark of Tolmar
Pharmaceuticals, Fort Collins, Colo. found in H. B. Ravivarapu, K.
L. Moyer, R. L. Dunn, International Journal of Pharmaceutics, 194
(2000) 181-191, which is incorporated in its entirety.
ATRIGEL.RTM., unless otherwise specified, comprises PLGA dissolved
in 1-methyl-2-pyrrolidinone (NMP).
[0091] The invention relates to a controlled release composition
comprising a gonadotropin-releasing hormone (GnRH) antagonist
(e.g., cetrorelix) loaded in a multi-block copolymer.
[0092] In one aspect, the inventor relates to a multi-block
copolymer composition having a gonadotropin-releasing hormone
(GnRH) antagonist (e.g., cetrorelix) as a bioactive agent. The
multi-block copolymer compositions are well known and fully
described in U.S. Pat. Nos. 8,481,651; 8,674,032; 8,674,033; and
9,364,442 and U.S. Application Publications 2013/0209568;
2013/0273284; and 2014/0199385, and PCT International Application
Publications WO2005068533; WO2004007588; WO2012005594; and
WO2013015685, all of which are incorporated by reference herein in
their entirety.
[0093] The multi-block copolymer comprises one or more hydrolysable
segments. In one embodiment, the multi-block copolymer comprises
one or more randomly arranged hydrolysable segments. In another
embodiment, the multi-block copolymer comprises one or more
non-randomly arranged hydrolysable segments. In yet another
embodiment, the multi-block copolymer comprises one or more
alternatingly arranged hydrolysable segments. In yet another
embodiment, the multi-block copolymer comprises one or more
non-alternatingly arranged hydrolysable segments.
[0094] In some embodiments, the segments can be randomly and
non-alternatingly connected to each other by multi-functional chain
extenders.
[0095] In one example, the multi-block copolymer is amorphous at
human body conditions.
[0096] In an exemplary embodiment, the multi-block copolymer has a
glass transition temperature below body temperature at human body
conditions.
[0097] In another aspect, the multi-block copolymer includes
pre-polymer A, pre-polymer B, or a combination thereof. In one
embodiment, pre-polymers A and B are composed of different
monomers. In another embodiment, pre-polymers A and B are composed
of the same monomers but in a different amount. In yet another
embodiment, the pre-polymers are composed of the same monomers but
with a different initiator in order to obtain the multi-block
copolymers of the present invention. In one embodiment the
multi-block copolymer is comprised of pre-polymers A and B which
are the same monomer with the same initiators.
[0098] Pre-polymers A and B can be selected in such a way that the
segments would exhibit significantly different properties, for
example, but not limited to thermal, degradation and hydrophilic
properties.
[0099] The pre-polymers A or B may comprise a hydrolysable
polyester, poly ether ester, polycarbonate, polyester carbonate,
polyanhydride or copolymers thereof. The pre-polymers can be
derived from cyclic monomers such as lactide (L, D or L/D),
glycolide, .epsilon.-caprolactone, .delta.-valerolactone,
trimethylene carbonate, tetramethylene carbonate,
1,5-dioxepane-2-one, 1,4-dioxane-2-one (para-dioxanone) or cyclic
anhydrides (oxepane-2,7-dione).
[0100] In one embodiment, the pre-polymer includes an ester
linkage. In another embodiment, pre-polymer includes a carbonate
linkage. In yet another embodiment, pre-polymer includes an
anhydride linkage. In some embodiments, pre-polymer optionally
comprises a polyether group. In an exemplary embodiment, polyether
is present as an additional pre-polymer.
[0101] In one example, pre-polymer comprises a reaction product of
an ester forming monomer. The ester forming monomer can be selected
from the group consisting of diols, dicarboxylic acids and
hydroxycarboxylic acids.
[0102] In another example, pre-polymer comprises reaction products
of at least one suitable cyclic monomer with at least one
non-cyclic initiator. The non-cyclic initiator can be selected from
the group consisting of diols, dicarboxylic acids and
hydroxycarboxylic acids.
[0103] Examples of cyclic monomers include, but are not limited to,
glycolide, lactide (L, D or DL), .epsilon.-caprolactone,
.delta.-valerolactone, trimethylene carbonate, tetramethylene
carbonate, 1,4-dioxane-2-one (para-dioxanone), 1,5-dioxepane-2-one
and cyclic anhydrides.
[0104] In some embodiments, the pre-polymer comprises at least two
different cyclic monomers. In one example, pre-polymer comprises
glycolide and .epsilon.-caprolactone in a 1:1 weight ratio. In
another example, pre-polymer comprises glycolide and lactide in a
1:1 weight ratio.
[0105] Examples of non-cyclic initiator include, but are not
limited to, succinic acid, glutaric acid, adipic acid, sebacic
acid, lactic acid, glycolic acid, hydroxybutyric acid, ethylene
glycol, diethylene glycol, 1,4-butanediol and 1,6-hexanediol.
[0106] Examples of polyether groups include, but are not limited
to, PEG (polyethylene glycol), PEG-PPG (polypropylene glycol), PTMG
(polytetramethylene ether glycol) and combinations thereof. In a
particular embodiment, the polyether group is PEG. PEG can be an
initiator for ring-opening polymerization. PEG with any suitable
molecular weight can be used, for example, a molecular weight
between 150-40000. In one embodiment, each of pre-polymers A and B
has a number average molecular weight between 300 and 30000.
[0107] In a particular embodiment, the composition comprises a
polyethylene glycol (PEG). Any suitable PEG known to one of skilled
in the art can be used. In an exemplary embodiment, PEG is
polyethylene glycol 200, polyethylene glycol 300, or methoxy
polyethylene glycol 350.
[0108] The chain-extender of the invention can be any suitable
multifunctional chain extender, known to one of skilled in the art.
In one embodiment, the pre-polymers are linked by the di-functional
chain-extender. Examples of di-functional chain-extender include,
for example, but are not limited to, a diisocyanate chain-extender,
a diacid and a diol compound.
[0109] The amount of pre-polymer, in the composition, can be any
suitable amount, known to one of skilled in the art. The amount, in
the composition, may be of about 10-90 wt. %.
[0110] The methods for synthesis of pre-polymers and multi-block
copolymer compositions are well known and fully described in U.S.
Pat. Nos. 8,481,651; 8,674,032; 8,674,033; and 9,364,442 and U.S.
Application Publications 2013/0209568; 2013/0273284; and
2014/0199385, and PCT International Application Publications
WO2005068533; WO2004007588; WO2012005594; and WO2013015685.
[0111] The intrinsic viscosity also may vary depending on one or
more desired properties. In some embodiment, the intrinsic
viscosity is larger than about 0.1 dl/g and less than about 6 dl/g.
In one embodiment, the intrinsic viscosity lies between about 0.2-4
dl/g, more preferably between 0.4-2 dl/g.
[0112] In another aspect, the invention relates to phase separated
multi block copolymers. The term "phase-separated," as used herein,
may refer to a system, for example, a copolymer having two or more
different pre-polymers, of which at least two are incompatible with
each other at temperatures of 40.degree. C. or below (when kept at
body conditions). As a result, the pre-polymers do not form a
homogeneous mixture when combined as a physical mixture or chemical
mixture.
[0113] The phase separated multi block copolymers are well known in
the art and fully described in U.S. Pat. Nos. 9,364,442 and
8,674,033, and PCT International Application Publications
WO2012005594 and, WO2004007588. The phase-separated quality of the
copolymers of the present invention is reflected in the profile of
the glass transition temperature (Tg), melting temperature (Tm), or
a combination thereof. For example, the phase-separated copolymers
are characterized by at least two-phase transitions, each of which
is related to (but not necessarily identical to) the corresponding
Tg or Tm values of the prepolymers which are comprised in the
copolymer. In an exemplary embodiment, the multi-block copolymer is
a phase separated multiblock copolymer, comprising: one or more
segments of a pre-polymer A (e.g., a linear soft biodegradable
pre-polymer A) having a glass transition temperature (T.sub.g)
lower than 37.degree. C.; and one or more segments of a pre-polymer
B (e.g., a linear hard biodegradable pre-polymer B) having a
melting point temperature (T.sub.m) ranging from about 40.degree.
C. to about 100.degree. C.
[0114] In another aspect, the invention relates to a composition,
the composition comprising: a therapeutically effective amount of a
cetrorelix in combination with a multi-block copolymer, wherein the
multi-block copolymer comprises randomly or non-alternatingly
arranged hydrolysable segments, wherein each segment comprises
pre-polymer A or pre-polymer B, and wherein the segments are
operably linked to each other by a multifunctional chain extender.
In an exemplary embodiment, the multi-block copolymer is a phase
separated multiblock copolymer, comprising: one or more segments of
a linear soft biodegradable pre-polymer A having a glass transition
temperature (T.sub.g) lower than 37.degree. C.; and one or more
segments of a linear hard biodegradable pre-polymer B having a
melting point temperature (T.sub.m) of 40-100.degree. C.
[0115] The multi-block copolymer compositions may be in any
suitable form, for example, in the form of implant, microspheres,
microrods, microparticles, injectable gel formulation, coatings or
membranes or devices, or any other form known in the art.
[0116] In a particular embodiment, the composition forms of a
hydrogel. In another particular embodiment, the composition is in
the form of microspheres. In particular embodiments, the
microspheres are loaded with a GnRH antagonist (e.g., cetrorelix)
and without salt.
[0117] In another aspect, the invention relates to the use of salt
bridges or cyclization of the active agent either as a primary drug
delivery technique or in combination with another drug delivery
vehicle using compounds that include, but are not limited to,
lanthionine, dicarba, hydrazine, or lactam bridges. The formation
of salt bridges for linking through non-covalent bonds are well
known in the art and fully described in PCT International
application publications WO2009/155257 and WO 2012/163519, which
are incorporated by reference herein in their entirety.
[0118] In another aspect, the invention relates to the use of
micronization or stabilizing adjuvants for a long-term delivery of
a GnRH antagonist. Micronization techniques are well known in the
art and fully described, for example, in PCT International
Application Publication WO2011/034514 and U.S. Application
Publication US2014/0219954, all of which are incorporated by
reference herein in their entirety. Stabilizing adjuvants are also
well known in the art and fully described, for example, in U.S.
Pat. No. 7,611,709, which is incorporated by reference herein in
its entirety.
[0119] In another aspect, the invention relates to the use of a
solid-in-oil-in-water (S/O/W), a water-in-oil-in water (W/O/W), or
a water-oil (W/O) production method for long term delivery of a
GnRH antagonist. These methods are well known in the art and fully
described, for example, in PCT International Application
Publications WO2015/145353; WO2003/099262; and WO2007/129926 and
U.S. Application Publications US2002/0055461; US2008/0268004; and
US2010/0019403, which are incorporated by reference herein in their
entirety.
[0120] In an exemplary embodiment, the composition achieves a
therapeutic effect within 24 hours and maintains therapeutic effect
for at least 180 days in, for example, >95% percent of treated
patients. In another embodiment, the composition achieves a
therapeutic effect within 24 hours and maintains therapeutic effect
for at least 133 days in, for example, >95% percent of treated
patients. In alternate embodiments, the composition achieves a
therapeutic effect within 7 days and maintains the therapeutic
effect for at least 90 days in, for example, >95% percent of
treated patients.
[0121] Microspheres for sustained release of therapeutically active
agents and methods of their preparations are well known in the art
(see e.g. U.S. Pat. Nos. 6,458,387 and 9,381,159 which are
incorporated by reference herein in their entirety). The
microspheres typically comprise a matrix formed of biodegradable
polymer. In some embodiments, the inner matrix diffuses through the
outer surface under appropriate conditions. In some embodiments,
the outer surface not only enables aqueous fluids to enter the
microsphere, but also enables solubilized drug and polymer to exit
the microsphere. The microspheres are made to release drug and
polymer from the interior of the microsphere when placed in an
appropriate aqueous medium, such as body fluids or a
physiologically acceptable buffer under physiological conditions
over a prolonged period of time, thereby providing sustained
release of a drug. In one embodiment, the microspheres are made to
release a drug without an initial burst or rapid drug release.
[0122] The microspheres have a generally uniform size
(substantially spherical) and shape, with each preparation having a
narrow size distribution. Microspheres range in size from about 0.5
microns to about 100 microns, depending upon the fabrication
conditions. The characteristics of the microspheres may be altered
during preparation by manipulating the water-soluble polymer
concentration, reaction temperature, pH, concentration of
therapeutic agent, crosslinking agent, and/or the length of time
the macromolecule is exposed to the crosslinking agent and/or the
energy source. In one example, microspheres are suitable for oral
or parenteral administration; mucosal administration; ophthalmic
administration; intravenous, subcutaneous, intra articular, or
intramuscular injection; administration by inhalation; or topical
administration.
[0123] In one embodiment the microsphere size is between 20-90
.mu.m. In another embodiment the microsphere size is between 30-80
.mu.m. In another embodiment the microsphere size is between 45-70
.mu.m.
[0124] The amount of polymer matrix, in the microsphere
composition, can be any suitable amount, known to one of skilled in
the art. The amount in the microsphere composition, may range from
about 10 wt. % to about 50 wt. %; from about 20 wt. % to about 40
wt. %; from about 25 wt. % to about 35 wt. %. In a particular
embodiment, the amount is approximately 10, 20, 25, 30, 35, 40, 45,
or 50 wt. %.
[0125] The amount of therapeutic molecule in the microsphere ranges
from about 1 wt. % to about 90 wt. %, from about 1 wt. % to about
40 wt. %, from about 3 wt. % to about 30 wt. %, from about 5 wt. %.
to about 20 wt. %, from about 10 wt. %. to about 15 wt. %. In a
particular embodiment, the amount is approximately 1, 3, 5, 7, 9
10, 15 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, or 90 wt. %.
[0126] In one embodiment the therapeutic molecule is loaded between
5% and 20% weight/weight. In another embodiment the therapeutic
molecule is loaded between 7% and 13% weight/weight.
[0127] In one embodiment the C.sub.max (maximum concentration in
the blood stream) is between 100 ng/ml and 400 ng/ml, or between
200 ng/ml and 350 ng/ml. More preferably between 275 ng/ml and 325
ng/ml.
[0128] In one embodiment the area under the curve (the curve of the
drug concentration in blood plasma vs. time) (AUC) is between 10000
ng/mL*hr and 30000 ng/mL*hr. In another embodiment the AUC is
between 12500 ng/mL*hr and 25000 ng/mL*hr. In another embodiment
the AUC is between 15000 ng/mL*hr and 20000 ng/mL*hr.
[0129] In one embodiment the amount of cetrorelix released after
one-and-a-half months is between 5% and 25% of the total amount of
cetrorelix. In another embodiment the amount of cetrorelix released
at this time is between 10% and 20% of the total amount of
cetrorelix. In another embodiment the amount of cetrorelix released
is between 12% and 15% of the total amount of cetrorelix.
[0130] In one embodiment the polymer is loaded at 15%-45%
weight/weight. In another embodiment the polymer is loaded at
25%-35% weight/weight.
[0131] In one aspect, the composition of the invention is an
injectable composition, which is administered with one injection or
two injections administered either concurrently or consecutively,
with a total injection volume of less than 4 mL. The injection may
be subcutaneous or intramuscular. The GnRH antagonist and polymer
may be stored in solution or suspension in a solvent suitable to
create a stable formulation for storage in a prefilled syringe. The
syringe may contain a GnRH antagonist, such as cetrorelix, in an
amount of about 50 mg to about 300 mg or about 50 mg to about 150
mg.
[0132] The invention also relates to a kit, wherein the kit
comprising: the composition of the invention.
[0133] In another aspect, the composition of the invention is
prepared with over 75% encapsulation/incorporation efficiency, and
exhibits consistent release of the active agent from the drug
delivery vehicle with no more than 25% variation. In yet another
aspect, the composition of the invention releases the active agent
from the drug delivery vehicle with >85% intact over the entire
duration of release.
[0134] In a further aspect, the invention relates to a method of
extending release of a pharmaceutical agent (e.g. cetrorelix) in a
subject for a period ranging from about 1 month to about 6 months
or about 1 month to about 9 months or greater than 9 months. The
method comprising administering to the subject a composition of the
invention (e.g. microspheres or gel). In another aspect, the
invention relates to a method of extending the release of a
pharmaceutical agent (e.g. cetrorelix) in a subject for a period of
at least 90 days, the method comprising administering to the
subject a composition of the invention (e.g. microspheres).
[0135] In a yet further aspect, the invention relates to a method
of maintaining an effective level of a therapeutic agent (e.g.
cetrorelix) in a subject for a period ranging from about 1 month to
about 6 months or from about 1 month to about 9 months or greater
than 9 months. The method comprising administering to the subject a
composition of the invention (e.g. microspheres or gel). In another
aspect, the invention relates to a method of maintaining an
effective level of a therapeutic agent (e.g. cetrorelix) in a
subject for a period at least 90 days, the method comprising
administering to the subject a composition of the invention (e.g.
microspheres).
[0136] In yet another aspect, the invention relates to a method for
treating a disease or condition associated with GnRH, the method
comprising administering a therapeutically effective amount of the
composition of the invention, thereby treating the disease in the
subject.
[0137] Effective doses of the compositions of the present
invention, for treatment of conditions or diseases as described
herein vary depending upon many different factors, including means
of administration, target site, physiological state of the patient,
whether the patient is human or an animal, other medications
administered, and whether treatment is prophylactic or therapeutic.
Usually, the patient is a human, however non-human mammals,
including transgenic mammals, can also be treated. Treatment
dosages may be titrated using routine methods known to those of
skill in the art to optimize safety and efficacy.
[0138] The pharmaceutical compositions of the invention may include
a "therapeutically effective amount." A "therapeutically effective
amount" refers to an amount effective, at dosages and for periods
of time necessary, to achieve the desired therapeutic result. A
therapeutically effective amount of a molecule may vary according
to factors such as the disease state, age, sex, and weight of the
individual, and the ability of the molecule to elicit a desired
response in the individual. A therapeutically effective amount is
also one in which any toxic or detrimental effects of the molecule
are outweighed by the therapeutically beneficial effects.
[0139] The compositions of the invention described herein can be
used to treat any GnRH associated disease or condition that could
be treated by GnRH antagonist in humans or animals. Examples of
treatments, for diseases or conditions treated by the compositions
of the invention include, for example, but are not limited to,
suppression of testosterone production, as well as suppression of
the hormones FSH and/or LH for the treatment of prostate cancer,
especially hormone sensitive prostate cancer, and benign prostatic
hyperplasia, directly blocking GnRH receptors on prostate cells for
treatment of prostate cancer and benign prostatic hyperplasia,
controlled ovarian stimulation for assisted reproductive
techniques, treatment of uterine myoma, suppression of ovarian
function while undergoing chemotherapy, treatment of breast cancer,
treatment of ovarian cancer, male contraception, and female
contraception.
[0140] As used herein, the terms "treat" and "treatment" refer to
therapeutic treatment, including prophylactic or preventative
measures, wherein the object is to prevent or slow down (lessen) an
undesired physiological change associated with a disease or
condition. Beneficial or desired clinical results include, but are
not limited to, alleviation of symptoms, diminishment of the extent
of a disease or condition, stabilization of a disease or condition
(i.e., where the disease or condition does not worsen), delay or
slowing of the progression of a disease or condition, amelioration
or palliation of the disease or condition, and remission (whether
partial or total) of the disease or condition, whether detectable
or undetectable. "Treatment" can also mean prolonging survival as
compared to expected survival if not receiving treatment. Those in
need of treatment include those already with the disease or
condition as well as those prone to having the disease or condition
or those in which the disease or condition is to be prevented. The
methods of treatment described herein can be used to treat any
suitable mammal, including primates, such as monkeys and humans,
horses, cows, cats, dogs, rabbits, elk, deer and rodents such as
rats and mice. In one embodiment, the mammal to be treated is
human.
[0141] "Administration" to a subject is not limited to any
particular delivery system and may include, without limitation,
parenteral (including subcutaneous, intravenous, intramedullary,
intraarticular, intramuscular, or intraperitoneal injection).
[0142] The composition of the invention may be administered
parenterally (e.g., intravenous, subcutaneous, intraperitoneal, and
intramuscular). Further, the composition of the invention may be
administered by intravenous infusion or injection. The composition
of the invention may be administered by intramuscular or
subcutaneous injection. In some embodiments, the composition of the
invention may be administered surgically. As used herein, a
"composition" refers to any composition that contains a
pharmaceutically effective amount of one or more active ingredients
(e.g., a GnRH antagonist). The composition, when administered to a
subject (human or animal) induces a desired pharmacological and/or
physiologic effect by local and/or systemic action.
[0143] The terms "subject," "individual," and "patient" are used
interchangeably herein, and refer to an animal, for example a
human, to whom treatment, including prophylactic treatment, with
the pharmaceutical composition according to the present invention,
is provided. The term "subject" as used herein refers to human and
non-human animals. The terms "non-human animals" and "non-human
mammals" are used interchangeably herein and include all
vertebrates, e.g., mammals, such as non-human primates,
(particularly higher primates), sheep, dog, rodent, (e.g. mouse or
rat), guinea pig, goat, pig, cat, rabbits, cows, horses and
non-mammals such as reptiles, amphibians, chickens, and
turkeys.
[0144] All patents and literature references cited in the present
specification are hereby incorporated by reference in their
entirety.
EXAMPLES
Example 1
[0145] Poly(DL-lactide-co-glycolide) with 1:1 ratio of lactide to
glycolide is dissolved in a suitable solvent to prepare an
Atrigel.RTM. polymer solution. This solution is then filled into a
syringe with a female luer lock fitting.
[0146] Each GnRH antagonist (ozarelix, degarelix, cetrorelix, or
ganirelex) is then dissolved in water or other solvents and filled
into a syringe with a male luer-lock fitting.
[0147] Prior to administration, the two syringes are coupled, and
the contents are mixed back and forth between the two syringes for
multiple cycles. After thorough mixing, the formulation is drawn
back into the syringe with the male coupling.
[0148] Then, the two syringes are separated and a needle is
attached. The contents of the syringe is then subcutaneously
injected into subjects. A total injection volume would be less than
4 mL per syringe and per injection.
[0149] Serum is then collected and analyzed. The GnRH antagonist
composition may achieve a therapeutic effect within 24 hrs and
maintain therapeutic effect for at least 90 days in >95% percent
of treated patients.
[0150] The composition is prepared with an encapsulation efficiency
of over 70% and may allow for consistent release of the active
agent from the drug delivery vehicle with no more than 25%
variation. The composition may release the active agent from the
drug delivery vehicle with >85% intact over the entire duration
of release.
Example 2
[0151] A multi-block copolymer is provided. Each GnRH antagonist
(ozarelix, degarelix, cetrorelix, or ganirelex) is loaded into the
multi-block copolymer. The formulation may be in the form of
microspheres.
[0152] The formulation would be subcutaneously injected into
subjects. A total injection volume would be less than 4 mL.
[0153] Serum is then collected and analyzed. The GnRH antagonist
composition may achieve a therapeutic effect within 24 hours and
maintain therapeutic effect for at least 90 days in >95% percent
of treated patients.
[0154] The composition may allow for consistent release of the
active agent from the drug delivery vehicle with no more than 25%
variation plus an encapsulation efficiency of over 70%. The
composition may release the active agent from the drug delivery
vehicle with >85% intact over the entire duration of
release.
Example 3
Development of Cetrorelix Microspheres Formulations and Testing
[0155] Several formulations of microspheres (MSP) using different
polymers and internal water phase compositions were prepared for
testing cetrorelix in vitro release (IVR). The tested formulations
are summarized in Table 1.
TABLE-US-00001 TABLE 1 Initial cetrorelix formulations CRX
Theoretical Loading Microsphere CRX measured MSP Microsphere size
(D50) loading by EAS Batch Process Polymer morphology (.mu.m) (Wt.
%) (Wt. %) EE (%) AD17-008 W1/O/W2 10CP10C20-323 Spherical, 40 12.5
11 88.5 (W1 = Acetic monodispersed acid/H.sub.2O 50/50) RP17-004
W1/O/W2 10CP10C20-323 Spherical, 73 14.3 13.8 96.5 (W1 = Acetic
monodispersed acid/H.sub.2O 35/65 pre-mix) RP17-006 W1/O/W2
10LP10L20-LL40 Spherical, 71 14.0% 14.8 105.4 (W1 = Acetic
monodispersed acid/H.sub.2O 35/65 pre-mix)
[0156] The in vitro release of cetrorelix was tested by incubating
microsphere formulations listed in Table 1 in 0.05 M Tris Buffer
with 5% BSA, pH 7.4 at 37.degree. C. The results show the release
was slowest when premixed 35% Acetic acid/65% H.sub.2O as internal
water phase was used (FIG. 1) in the microsphere preparation
process.
[0157] To further test cetrorelix IVR, several formulations of
cetrorelix-loaded microspheres using different polymers and 35%
Acetic acid/65% H.sub.2O as internal water phase were made as
illustrated in Table 2.
TABLE-US-00002 TABLE 2 Cetrorelix formulations manufactured with
optimizing primary emulsification process (W1 = 35/65 Acetic
acid/Water mixture) CRX Theoretical Loading MSP Micro sphere MSP
size CRX loading measured by Batch Process Polymer morphology (D50)
(.mu.m) (Wt. %) EAS (Wt. %) EE (%) RP17-012 W1/O/W2 10CP10C20-D23
Spherical, 82 15.70% 13.5 85.70% monodispersed RP17-013 W1/O/W2
20CP15C50-D23 Spherical, 85 14.00% 13.4 95.70% monodispersed
RP17-014 W1/O/W2 20LP10C20-LL40 Spherical, 70 13.90% 13.6 97.80%
monodispersed RP17-015 W1/O/W2 20CP10C20-LL40 Spherical, 56 13.20%
11.9 90.90% monodispersed RP17-018 W1/O/W2 30CP15C50-D23 Spherical,
51 13.80% 9.5 68.40% monodispersed
[0158] The in vitro release of cetrorelix was tested by incubating
the microsphere formulations listed in Table 2 in 0.05 M Tris
Buffer with 5% BSA, pH 7.4 at 37.degree. C. The results show that
the RP17-014 formulation using 20LP10C20-LL40 polymer had the
slowest cetrorelix release rate, and, in addition showed linear
release kinetics (FIG. 2), while RP17-012 (10CP10C20-D23) and
RP17-013 (20CP15C50-D23) microsphere formulations (depicted in
electron micrographs in FIG. 4A and FIG. 4B respectively) provided
the highest sustained daily dose of cetrorelix (FIG. 3).
[0159] These results show that slow degrading L-Lactide based
polymers with low swellability are suitable for use in
cetrorelix-loaded microspheres and display linear cetrorelix
release. In addition, the microsphere manufacturing process
achieves cetrorelix drug load of up to 15% by weight.
Example 4
Cetrorelix-Loaded Gel Pharmacokinetics in Rats
[0160] Several salt-free cetrorelix PLGA formulations having
different polymer contents were tested in a rat PK Study
(compositions outlined in Table 3). The preparations (<1 ml)
were subcutaneously implanted into rats at a single 20 mg/kg dose
and cetrorelix levels in plasma were monitored over 6 weeks. The
results are summarized in Table 4. All formulations showed
detectable plasma cetrorelix for greater than 42 days.
C.sub.max/C.sub.ave,42day varied from 12.1 to 17.6 and the
percentage of day 1 release related to the full 42 days ranged from
12 to 17% (FIG. 5). The amount of the polymer in the formulation
(20% to 40% by weight) did not have an appreciable effect on the
duration of release over the 42 days, but, did alter the amount of
initial release from the formulation.
TABLE-US-00003 TABLE 3 Salt-free cetrorelix PLGA formulation
compositions Theo. Cetrorelix PLGA Total Cetrorelix RG502H RG752H
NMP Total Loading Solution Solid ID (mg) (mg) (mg) (mg) (mg) (%,
w/w) (%, w/w)* (%, w/w) VH-022-001 365.5 677.22 0.0 2688 3730.4 9.8
20.1% 28.0 VH-023-001 291.3 408.28 405.7 1885 2990.5 9.7 30.2% 37.0
VH-024-001 291.5 0.0 1084.6 1618 2993.6 9.7 40.1% 46.0 *PLGA (%,
w/w) = PLGA wt / (PLGA wt + Total Solvent wt)
TABLE-US-00004 TABLE 4 Salt-free cetrorelix PLGA formulation rat
pharmacokinetic results C.sub.max T.sub.max AUC.sub.0-42 day
C.sub.ave, 42 day C.sub.max/ AUC.sub.0-24 hr AUC.sub.0-24 hr/ ID
(ng/mL) (hr) (ng/mL * hr) (ng/mL) C.sub.ave, 42 day (ng/mL * hr)
AUC.sub.0-42 day VH-022-001 283.7 1 16272.7 16.1 17.6 2761.9 17.0%
VH-023-001 218.7 1 18270.5 18.1 12.1 2206.9 12.1% VH-024-001 218.7
1 16406.1 16.3 13.4 2191.0 13.4%
Example 5
Salt Compositions of Cetrorelix
[0161] The pharmacokinetics of cetrorelix formulations of either Ca
Pamoate or Na Oleate salt were tested in rats through
subcutaneously implanting a single 5 mg/kg salt suspension in a
vehicle solution (20 mM K-Phos Buffer, 2.5% Mannitol, 3.5% CMC,
0.1% PS80) and monitoring cetrorelix levels in plasma over 6 weeks.
The results are summarized in Table 5 and FIGS. 6A and 6B. All
formulations showed detectable plasma cetrorelix for greater than
42 days. C.sub.max/C.sub.ave,42day varied from 2.4 to 3.1 and the
percentage of day 1 release related to 42 days about 11%.
TABLE-US-00005 TABLE 5 Salt-containing cetrorelix formulations rat
pharmacokinetic results. C.sub.max T.sub.max AUC.sub.0-42 day
C.sub.ave, 42 day C.sub.max/ AUC.sub.0-24 hr AUC.sub.0-24 hr/ ID
(ng/mL) (hr) (ng/mL * hr) (ng/mL) C.sub.ave, 42 day (ng/mL * hr)
AUC.sub.0-42 day Group 4 - 19.6 8 3444.0 3.4 3.1 376.9 10.9% Salt
Ca Pamoate Group 5 - 17.5 8 3331.9 3.3 2.4 361.1 10.8% Salt Na
Oleate
[0162] There was no principal difference between pharmacokinetics
of the two cetrorelix salt compositions in the initial 24 hour
initial release (FIG. 6B) and over the long term (FIG. 6A).
Moreover, while salt compositions of cetrorelix resulted in lower
plasma cetrorelix compared to the salt free formulations in the
long term (FIG. 7A), this difference could be attributable to the
different dose (FIG. 8). However, dose difference did not account
for the far greater peak concentration observed during the initial
release phase with cetrorelix in PLGA formulations. Indeed, the
salt composition all but eliminated the initial release peak that
was observed in PLGA formulations (FIG. 7B).
[0163] The downstream physiological effects of cetrorelix
microspheres administration were assessed through monitoring
testosterone levels in rats. All the formulations caused notable
drop in serum testosterone levels after 24 hours (FIG. 9B). These
low levels were maintained for the entire 6 weeks monitoring period
in all rats except those treated with Na Oleate salt compositions
(FIG. 9A).
[0164] The total amount of cetrorelix released was assessed using
the method of Schwahn et al., Drug Metabolism & Disposition,
Vol. 28, No. 1, p 10, incorporated by reference, assuming rat
weight ranging from 250 to 400 g, 10 mg/kg dose, and AUC
(ng/mL*hr)=618.1.
[0165] Based on these assumptions, AUC for 20 mg/kg dose (ng/mL*hr)
was assumed to be 123,620 and AUC for 5 mg/kg dose (ng/mL*hr) was
assumed to be 30,905. The calculations based on the above
assumptions resulted in estimated percentage of cetrorelix released
(up to 42 days) ranging from 11 to 15% of the amount initially
present in the microspheres. (See Table 6). These results clearly
show that the salt compositions have a lower initial release
compared to cetrorelix in PLGA alone.
TABLE-US-00006 TABLE 6 Summary of pharmacokinetic data for
cetrorelix salt and PLGA formulations. Est. % Cetrorelix Dose
C.sub.max T.sub.max AUC.sub.0-42 day Released ID PLGA (mg/kg)
(ng/mL) (hr) (ng/mL * hr) (up to 42 days) VH-022-001 RG502H, 20% 20
283.7 1 16272.7 13.2 VH-023-001 RG502H/RG752H, 30% 20 218.7 1
18270.5 14.8 VH-024-001 RG752H, 40% 20 218.7 1 16406.1 13.3 Group 4
- Salt Ca Pamoate 5 19.6 8 3444.0 11.1 Group 5 - Salt Na Oleate 5
17.5 8 3331.9 10.8
Example 6
In Vitro Cetrorelix Release Studies of Cetrorelix Salt Compositions
in PLGA Formulations
[0166] To supplement the in vivo pharmacokinetic data and further
optimize the compositions of cetrorelix in PLGA, in vitro release
studies were carried out wherein 45 mg of cetrorelix were incubated
in 0.5 ml Tris Mannitol, pH 7.4 at 37.degree. C. The results for in
vitro release for the salt-free formulations used in
pharmacokinetic studies are summarized in FIG. 10. In contrast to
the in vivo data, the increase of PLGA content in the composition
from 20% to 30% resulted in marked reduction of cetrorelix release
rate and of cumulative release. Surprisingly, further increase of
PLGA content from 30% to 40%, while resulting in further decrease
in release rate, also yielded negligible change in cumulative
release levels, especially in the long term. Moreover, in all
formulations the cumulative release appears to plateau after about
60 days suggesting that the maximum cumulative release has been
achieved.
[0167] In order to further explore the effect of salt composition
on cetrorelix release, several salt compositions of cetrorelix were
prepared as formulations in 30% total PLGA solution (1:1 ratio of
RG502H (50:50 lactide:glycolide) and RG752H (75:25
lactide:glycolide)) (Table 7), then tested and compared with
salt-free PLGA formulations.
TABLE-US-00007 TABLE 7 Salt-containing RG502H/RG752H (30% PLGA)
cetrorelix formulations Cetrorelix Cetrorelix Cetrorelix PLGA Salt
Content PLGA* NMP Total Loading Solution Total Solid ID Salt (mg)
(%, w/w) (mg) (mg) (mg) (%, w/w) (%, w/w) (%, w/w) Form-N Ca
Pamoate 63.29 77% 135.0 316.3 514.6 9.5 29.9 38.5 Form-P Na Oleate
58.80 83% 134.7 317.4 510.9 9.6 29.8 37.9 Form-R Ca Citrate 62.20
78% 134.9 316.5 513.6 9.4 29.9 38.4 *PLGA = 50:50 RG752H:RG502H
(w:w)
[0168] The results show that the presence of salt markedly
decreases cumulative cetrorelix release levels (FIG. 11). While Na
Oleate was particularly effective, all salts resulted in lower
cumulative release compared to the corresponding salt free
composition. In addition, cetrorelix cumulative release in the case
of salt compositions appeared to reach a plateau after 49 days. At
the same time Na Oleate and Ca Citrate did not appear to have any
effect on the initial release rate. The presence of Ca Pamoate
decreased the initial release rate.
[0169] Surprisingly, when the polymer content was increased to 40%
and PLGA was RG752H (75:25 lactide:glycolide) (Table 8), the
presence of Ca Pamoate slowed the initial release rate but
dramatically (nearly 3-fold) increased cumulative cetrorelix
release, as compared with salt free formulation. On the other hand,
similarly to the RG502H/RG752H data, Na Oleate and Ca Citrate did
not appear to have any effect on the initial release rate although
these formulations displayed a modest increase in cumulative
release levels (FIG. 12).
TABLE-US-00008 TABLE 8 Salt-containing RG752H (40% PLGA) cetrorelix
formulations Cetrorelix Cetrorelix Cetrorelix PLGA Total Salt
Content RG752H NMP Total Loading Solution Solid ID Salt (mg) (%,
w/w) (mg) (mg) (mg) (%, w/w) (%, w/w) (%, w/w) Form-O Ca Pamoate
62.95 77% 180.5 268.4 511.8 9.5 40.2 47.6 Form-Q Na Oleate 58.53
83% 180.6 269.4 508.6 9.6 40.1 47.0 Form-S Ca Citrate 56.88 78%
166.2 246.5 469.5 9.4 40.3 47.5
[0170] To investigate the effect of polymer and
N-methyl-2-pyrrolidone (NMP) on cetrorelix release rate and
cumulative release, cetrorelix salt compositions were prepared in
formulations using 40% total PLGA (1:1 RG502H and RG752H) or 40%
RG752S (ester end capped), with NMP or DMSO as polymer solvent
(Table 9) were tested.
TABLE-US-00009 TABLE 9 Cetrorelix formulations with different
polymers and solvent at 40% total PLGA. RG502H + Cetrorelix PLGA
Total Cetrorelix RG752S RG752H NMP DMSO Total Loading Solution
Solid ID (mg) (mg) (mg)* (mg) (mg) (mg) (%, w/w) (%, w/w)** (%,
w/w) Form-J 45.3 167.43 0 257 0 470.1 9.6 39.4 45.3 Form-K 45.4
168.55 0 0 251 465.2 9.8 40.1 46.0 Form-L 45.6 0 166.98 252 0 464.2
9.8 39.9 45.8 Form-M 45.9 0 169.87 0 252 467.3 9.8 40.3 46.2
*RG502H:RG752H (w:w) = 50:50 **PLGA (%, w/w) = PLGA wt / (PLGA wt +
Total Solvent wt)
[0171] The results are summarized in FIG. 13 and Table 10.
Surprisingly, the NMP formulation of cetrorelix in 40% RG752S
resulted in a dramatic increase in both cetrorelix release rate and
total release as compared to the same formulation in DMSO solution.
Interestingly, the mixed polymer formulation in 40% total PLGA (1:1
mixture of RG502H and RG752H) displayed NMP-independent multiphasic
cetrorelix release profile consisting of initial burst phase
followed by a first plateau phase at about 8% cumulative release,
achieved on day 42, followed by the second release phase on days
42-49, and subsequently followed by a second plateau phase, at
approximately 17% cumulative release, achieved on day 92. The total
recovery from the formulation composition in the in vitro release
experiment is about 100% indicating that despite the seemingly
limited cumulative release for all formulations (<30%), the
cetrorelix remains intact within the depot formulations.
TABLE-US-00010 TABLE 10 Mass balance (total recovery) from in vitro
release data for 40% RG752S formulations in either NMP or DMSO ID
Total Release (%) Residual Loading (%) Total Recovery (%) Form-J
22.0 (743.3 .mu.g) 89.0 111.0 Form-K 11.1 (362.0 .mu.g) 89.4
100.2
Example 7
Cetrorelix Salt Compositions and Cetrorelix PLGA Formulations
Pharmacokinetics in Rats
[0172] Several salt-free cetrorelix-loaded gel formulations having
different polymer contents were used for PK Study (see Table 6 for
PLGA content of salt-free cetrorelix-loaded gel formulations). The
salt-free preparations (<1 ml) were subcutaneously implanted
into rats at a single 20 mg/kg dose and cetrorelix levels in plasma
were monitored over 17 weeks (119 days). The results are summarized
in Table 11 and FIG. 14. All formulations showed detectable plasma
cetrorelix .gtoreq.119 days. The percentage of day 1 release
related to 119 days ranged from 9 to 13%. Importantly, the amount
of polymer in the preparation did not seem to have any
statistically significant effect on cetrorelix release.
TABLE-US-00011 TABLE 11 Rat study results up to 119 days:
Pharmacokinetic data of salt-free and salt-containing cetrorelix
gel formulations Cetrorelix C.sub.max T.sub.max AUC.sub.0-119 day
AUC.sub.0-24 hr AUC.sub.0-24 hr/ ID Dose (mg/kg) (ng/mL) (hr)
(ng/mL * hr) (ng/mL * hr) AUC.sub.0-119 day VH-022-001 20 283.7 1
22,088.05 2761.9 12.5% Salt-free VH-023-001 20 218.7 1 25,418.35
2206.9 8.7% Salt-free VH-024-001 20 218.7 1 26,173.31 2191.0 8.4%
Salt-free Group 4 - Salt 5 19.6 8 4,359.27* 376.9 8.6%* Ca Pamoate
Group 5 - Salt 5 17.5 8 3,854.37* 361.1 9.4%* Na Oleate *Groups 4
and 5 had no plasma collected after 91 days.
[0173] In addition, pharmacokinetics of cetrorelix gel formulations
containing either Ca Pamoate or Na Oleate salt were tested in rats
through subcutaneously implanting a single 5 mg/kg gel dose in a
vehicle solution (20 mM K-Phos Buffer, 2.5% Mannitol, 3.5% CMC,
0.1% PS80) and monitoring cetrorelix levels in plasma for 91 days.
No plasma was collected after day 91 for rats into which cetrorelix
gel formulations containing either Ca Pamoate or Na Oleate salt
were implanted. (See Table 7 for salt-containing RG502H/RG752H (30%
PLGA) cetrorelix gel formulations). The results are summarized in
Table 11 and FIG. 14. All formulations showed detectable plasma
cetrorelix .gtoreq.over 7 weeks (.gtoreq.49 days). The percentage
of day 1 release related to 91 days was about 9%.
[0174] There was no principal difference between pharmacokinetics
of cetrorelix gel formulations containing Ca Pamoate and those
containing Na Oleate both in the initial 24 hour burst release
phase (FIG. 14) and over the long term (FIG. 14). Although,
salt-containing cetrorelix gel resulted in lower plasma cetrorelix
compared to the salt free formulations in the long term (FIG. 14),
this difference could be attributable to the different dose (FIG.
14 and Table 11). However, dose difference did not account for the
far greater peak concentration observed at the initial burst
release phase when salt free formulations were used. Indeed,
addition of salt all but eliminated the sharp peak observed in its
absence (FIG. 14).
[0175] The downstream physiological effects of cetrorelix gel
administration were assessed through monitoring testosterone levels
in rats. All the formulations caused notable drop in serum
testosterone levels after 24 hours (FIG. 15B). These low levels
were maintained for the entire 19 weeks monitoring period in all
rats except those treated with Na Oleate-containing microspheres,
whose testosterone levels began to increase after week 5 (FIG.
15A). In contrast, the testosterone levels of rats treated with the
Ca-Oleate began to increase after week 9 (FIG. 15A).
[0176] The total amount of cetrorelix released was assessed using
the method of Schwahn et al., Drug Metabolism & Disposition,
Vol. 28, No. 1, p 10, assuming rat weight ranging from 250 to 400
g, 10 mg/kg dose, and AUC (ng/mL*hr)=618.1.
[0177] Based on these assumptions, AUC for 20 mg/kg dose (ng/mL*hr)
was assumed to be 123,620 and AUC for 5 mg/kg dose (ng/mL*hr) was
assumed to be 30,905. The calculations based on the above
assumptions results in estimated percentage of cetrorelix released
(up to 119 days) ranging from 9 to 13% of the amount initially
present in the gel. (See Table 11).
Example 8
Enhancing the Level of Cetrorelix
[0178] To further explore the effect of polymer on cetrorelix
release, several formulations of cetrorelix in PLGA (Table 13) were
tested and compared within a second rat study and in dogs.
Variables were PLGA polymer type, peptide source, solvent, drug
load, and % PLGA in solution.
TABLE-US-00012 TABLE 13 Cetrorelix PLGA formulation compositions
Cetrorelix PLGA Loading Solution PLGA Type (%, (%, ID API Solvent
Solvent w/w) w/w) VH-023-003 CPC RG502H/ NMP 10.2 30.1% RG752H
VH-030-001 Hemmo RG752H NMP 10.2 29.9% VH-030-002 CPC RG752H NMP
10.1 29.9% VH-031-001 CPC RG752H NMP 9.9 25.1% VH-032-001 CPC
RG752H NMP 10.0 20.0% VH-033-001 CPC R202H NMP 10.6 30.0%
VH-034-001 CPC RG752H NMP 12.3 30.1% VH-035-001 CPC RG752H DMSO
10.1 30.0%
[0179] In a second rat study serum testosterone and cetrorelix
levels were measured over 12 weeks. FIG. 16A shows the testosterone
level in rats at 12 weeks. The formulations found within Table 13
were injected in rats and then the testosterone was measured at 0,
1, 2, 8 and 24 hours and then daily until the end of the first week
and then biweekly until week 4 and then weekly thereafter. As shown
in FIG. 16B, the level of testosterone dropped below 1 ng/ml within
8 hours and the level was maintained over 12 weeks with no
formulations showing break through (elevated testosterone).
[0180] FIG. 17 shows the cetrorelix levels in the 2.sup.nd rat
study over the same 12-week period. The levels of cetrorelix were
all above 2 ng/ml which is the level required to inhibit
testosterone production.
[0181] Three PLGA cetrorelix formulations were selected for further
testing of cetrorelix pharmacokinetics in dogs. Three cetrorelix
formulations that consisted of different PLGA/NMP solutions were
used: 20% RG752H (VH-032-002), 30% RG752H (VH-030-003), and 30%
R202H (VH-033-002). After the initial dose, the animals serum
concentration of cetrorelix was measured for 26 weeks. In all three
groups at least one animal still had a serum concentration above 2
ng/ml at 26 weeks as shown in FIG. 18A. FIG. 18B shows the
background levels of cetrorelix within the studies animals one week
prior to dosing, which was less than 0.5 ng/ml for all the
animals.
[0182] FIG. 19 compares the cetrorelix data from the 1.sup.st dog
trials to the 2.sup.nd rat trial up to 39 weeks. All three
formulations injected into the rats had quantifiable levels of
cetrorelix after 39 weeks as shown in FIG. 19A. Similarly, FIG. 19B
shows that the three formulations injected into the dogs in the
first trial had quantifiable levels of cetrorelix after 26 weeks.
The pharmacokinetic data is tabulated in FIG. 19C.
[0183] Serum testosterone data was collected in the 1.sup.st dog
trial to demonstrate efficacy of the cetrorelix in the formulation.
FIG. 20A shows the levels of testosterone the dogs had within each
group. All the dogs had quantifiable levels of testosterone one
week prior to injection, as shown in FIG. 20B, but after the
injection the animals only had a sustained quantifiable level of
testosterone starting at week 8 and some of the animals did not
have a quantifiable level of testosterone even after 26 weeks.
[0184] FIG. 21 compares the data from the 2.sup.nd rat and 1.sup.st
dog study results for testosterone levels. FIG. 21A shows that the
rats did not have a resurgence of testosterone for any of the
formulations until week 26. Whereas FIG. 21B shows that the dogs
started to regain testosterone after week 6, but it did take
several weeks for the animals to regain the levels they had before
the cetrorelix injection. The data is tabulated in FIG. 20A.
[0185] FIG. 22A shows the level of cetrorelix for the 19.9% RG752H
solution formulation in the 1st dog trial. The serum level of
cetrorelix stayed above 2 ng/ml until at least week 4 and for one
animal up to week 14. FIG. 22B shows the corresponding measured
level of serum testosterone for the same animals. As long as the
cetrorelix level was above 2 ng/ml, the testosterone level was
below the quantifiable limit for all three animals. Once cetrorelix
level drops below 2 ng/ml the testosterone level increased.
[0186] FIG. 23A shows the level of cetrorelix for the 30% RG752H
solution formulation in the 1.sup.st dog trial. The serum level of
cetrorelix stayed equal to or greater than 2 ng/ml until at least
week 4 and for one animal until week 14. FIG. 23B shows the
corresponding measured level of serum testosterone for the same
animals. As long as the cetrorelix level was above 2 ng/ml the
testosterone level was below the quantifiable limit for all three
animals. Once cetrorelix level drops below 2 ng/ml the testosterone
level increased.
[0187] FIG. 24A shows the level of cetrorelix for the 30% R202H
solution formulation in the 1.sup.st dog trial. The serum level of
cetrorelix stayed above 2 ng/ml until at least week 13 and for one
animal even after 26 week the level still was above 2 ng/ml. FIG.
24B shows the corresponding measured level of serum testosterone
for the same animals. As long as the cetrorelix level was above 2
ng/ml the testosterone level was below the quantifiable limit for
all three animals. Once cetrorelix level drops below 2 ng/ml the
testosterone level increased. Therefore, the animal whose level of
cetrorelix did not dip below 2 ng/ml did not experience an increase
in testosterone even after 26 weeks.
[0188] In sum, the results in FIGS. 16-24 demonstrate that
testosterone level goes up only once cetrorelix level drops less
than 2 ng/ml.
Example 9
Cetrorelix Deposit
[0189] A subject is injected with a depot injection, usually
subcutaneously that deposits the drug in a localized mass that is
gradually absorbed by the surrounding tissue. The depot injection
has a consistent release of the drug over a sustained period.
[0190] Cetrorelix, in any of the formulations described herein, is
injected subcutaneously as a depot, and the drug releases over at
least 90 days. There is an immediate suppression of testosterone,
without a concurrent surge upon the initial or repeated injection
of the formulation of cetrorelix.
Example 10
Prostate Cancer Treatment
[0191] In a clinical trial done with 50 adult-male, prostate cancer
subjects in an open label study. The subjects will have a
histologically confirmed diagnosis of adenocarcinoma of the
prostate. The subjects are stratified into 5 different categories
based on disease progression with each group having ten patients.
The groups will all be injected once with 0.375 g of the 45 mg
formulation subcutaneously.
[0192] The subjects will have their blood taken every week to have
the serum levels of cetrorelix and testosterone analyzed. Every 3
weeks, biopsies are performed to ascertain the size of the
adenocarcinoma of the prostate. It is assumed that as long as the
level of cetrorelix is above 2 ng/ml the levels of testosterone
within the subject would be extremely low, which will cause the
adenocarcinoma to shrink and the tumor to go into remission.
[0193] It will be appreciated by those skilled in the art that
changes could be made to the embodiments described above without
departing from the broad inventive concept thereof. It is
understood, therefore, that this invention is not limited to the
particular embodiments disclosed, but it is intended to cover
modifications that are within the spirit and scope of the
invention, as defined by the appended claims.
* * * * *